Radiofrequency (RF) communications, such as for mobile telephony, may use an RF power amplifier (PA) circuit in an RF transmitter to produce the RF signal for transmission over the air to an RF receiver. The PA circuit may have a nonlinear gain characteristic, such as gain compression occurring at higher power output levels, which can lead to signal distortion at such higher power levels.
U.S. Pat. No. 6,342,810, for example, mentions a method of compensating for amplifier nonlinearities by using predistortion to apply an inverse model of the amplifier's transfer characteristic to an input signal of the amplifier. A goal of such predistortion is to reduce distortion due to the PA circuit gain nonlinearity.